diff --git a/setup.py b/setup.py
index eedc3779..d615bdf4 100644
--- a/setup.py
+++ b/setup.py
@@ -59,7 +59,8 @@
         "p_docs": [
             # >= 3.2: https://github.com/sphinx-doc/sphinx/issues/8008
             # >= 3.2.1: https://github.com/sphinx-doc/sphinx/issues/8124
-            "sphinx >= 3.2.1",
+            # != 3.4.0, != 3.4.1: https://github.com/sphinx-doc/sphinx/issues/8567
+            "sphinx >= 3.2.1, != 3.4.0, != 3.4.1",
             "sphinx-autodoc-typehints",
             "sphinx-qt-documentation>=0.3",
             "sphinx_rtd_theme",